README
¶
null 
import "gopkg.in/guregu/null.v4"
null is a library with reasonable options for dealing with nullable SQL and JSON values
There are two packages: null and its subpackage zero.
Types in null will only be considered null on null input, and will JSON encode to null. If you need zero and null be considered separate values, use these.
Types in zero are treated like zero values in Go: blank string input will produce a null zero.String, and null Strings will JSON encode to "". Zero values of these types will be considered null to SQL. If you need zero and null treated the same, use these.
All types implement sql.Scanner and driver.Valuer, so you can use this library in place of sql.NullXXX.
All types also implement: encoding.TextMarshaler, encoding.TextUnmarshaler, json.Marshaler, and json.Unmarshaler. A null object's MarshalText will return a blank string.
null package
import "gopkg.in/guregu/null.v4"
null.String
Nullable string.
Marshals to JSON null if SQL source data is null. Zero (blank) input will not produce a null String.
null.Int
Nullable int64.
Marshals to JSON null if SQL source data is null. Zero input will not produce a null Int.
null.Float
Nullable float64.
Marshals to JSON null if SQL source data is null. Zero input will not produce a null Float.
null.Bool
Nullable bool.
Marshals to JSON null if SQL source data is null. False input will not produce a null Bool.
null.Time
Marshals to JSON null if SQL source data is null. Zero input will not produce a null Time.
zero package
import "gopkg.in/guregu/null.v4/zero"
zero.String
Nullable string.
Will marshal to a blank string if null. Blank string input produces a null String. Null values and zero values are considered equivalent.
zero.Int
Nullable int64.
Will marshal to 0 if null. 0 produces a null Int. Null values and zero values are considered equivalent.
zero.Float
Nullable float64.
Will marshal to 0.0 if null. 0.0 produces a null Float. Null values and zero values are considered equivalent.
zero.Bool
Nullable bool.
Will marshal to false if null. false produces a null Float. Null values and zero values are considered equivalent.
zero.Time
Will marshal to the zero time if null. Uses time.Time's marshaler.
Can you add support for other types?
This package is intentionally limited in scope. It will only support the types that driver.Value supports. Feel free to fork this and add more types if you want.
Can you add a feature that ____?
This package isn't intended to be a catch-all data-wrangling package. It is essentially finished. If you have an idea for a new feature, feel free to open an issue to talk about it or fork this package, but don't expect this to do everything.
Package history
As of v4, unmarshaling from JSON sql.NullXXX JSON objects (ex. {"Int64": 123, "Valid": true}) is no longer supported. It's unlikely many people used this, but if you need it, use v3.
Bugs
json's ",omitempty" struct tag does not work correctly right now. It will never omit a null or empty String. This might be fixed eventually.
License
BSD
Documentation
¶
Overview ¶
Package null contains SQL types that consider zero input and null input as separate values, with convenient support for JSON and text marshaling. Types in this package will always encode to their null value if null. Use the zero subpackage if you want zero values and null to be treated the same.
Index ¶
- type Bool
- func (b Bool) Equal(other Bool) bool
- func (b Bool) IsZero() bool
- func (b Bool) MarshalJSON() ([]byte, error)
- func (b Bool) MarshalText() ([]byte, error)
- func (b Bool) Ptr() *bool
- func (b *Bool) Scan(value interface{}) error
- func (b *Bool) SetValid(v bool)
- func (b *Bool) UnmarshalJSON(data []byte) error
- func (b *Bool) UnmarshalText(text []byte) error
- func (b Bool) ValueOrZero() bool
- type Float
- func (f Float) Equal(other Float) bool
- func (f Float) IsZero() bool
- func (f Float) MarshalJSON() ([]byte, error)
- func (f Float) MarshalText() ([]byte, error)
- func (f Float) Ptr() *float64
- func (f *Float) Scan(value interface{}) error
- func (f *Float) SetValid(n float64)
- func (f *Float) UnmarshalJSON(data []byte) error
- func (f *Float) UnmarshalText(text []byte) error
- func (f Float) ValueOrZero() float64
- type Int
- func (i Int) Equal(other Int) bool
- func (i Int) IsZero() bool
- func (i Int) MarshalJSON() ([]byte, error)
- func (i Int) MarshalText() ([]byte, error)
- func (i Int) Ptr() *int64
- func (i *Int) Scan(value interface{}) error
- func (i *Int) SetValid(n int64)
- func (i *Int) UnmarshalJSON(data []byte) error
- func (i *Int) UnmarshalText(text []byte) error
- func (i Int) ValueOrZero() int64
- type String
- func (s String) Equal(other String) bool
- func (s String) IsZero() bool
- func (s String) MarshalJSON() ([]byte, error)
- func (s String) MarshalText() ([]byte, error)
- func (s String) Ptr() *string
- func (s *String) Scan(value interface{}) error
- func (s *String) SetValid(v string)
- func (s *String) UnmarshalJSON(data []byte) error
- func (s *String) UnmarshalText(text []byte) error
- func (s String) ValueOrZero() string
- type Time
- func (t Time) Equal(other Time) bool
- func (t Time) ExactEqual(other Time) bool
- func (t Time) IsZero() bool
- func (t Time) MarshalJSON() ([]byte, error)
- func (t Time) MarshalText() ([]byte, error)
- func (t Time) Ptr() *time.Time
- func (t *Time) Scan(value interface{}) error
- func (t *Time) SetValid(v time.Time)
- func (t *Time) UnmarshalJSON(data []byte) error
- func (t *Time) UnmarshalText(text []byte) error
- func (t Time) Value() (driver.Value, error)
- func (t Time) ValueOrZero() time.Time
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Bool ¶
Bool is a nullable bool. It does not consider false values to be null. It will decode to null, not false, if null.
func BoolFromPtr ¶
BoolFromPtr creates a new Bool that will be null if f is nil.
func (Bool) IsZero ¶
IsZero returns true for invalid Bools, for future omitempty support (Go 1.4?) A non-null Bool with a 0 value will not be considered zero.
func (Bool) MarshalJSON ¶
MarshalJSON implements json.Marshaler. It will encode null if this Bool is null.
func (Bool) MarshalText ¶
MarshalText implements encoding.TextMarshaler. It will encode a blank string if this Bool is null.
func (Bool) Ptr ¶
Ptr returns a pointer to this Bool's value, or a nil pointer if this Bool is null.
func (*Bool) UnmarshalJSON ¶
UnmarshalJSON implements json.Unmarshaler. It supports number and null input. 0 will not be considered a null Bool.
func (*Bool) UnmarshalText ¶
UnmarshalText implements encoding.TextUnmarshaler. It will unmarshal to a null Bool if the input is blank. It will return an error if the input is not an integer, blank, or "null".
func (Bool) ValueOrZero ¶
ValueOrZero returns the inner value if valid, otherwise false.
type Float ¶
type Float struct {
sql.NullFloat64
}
Float is a nullable float64. It does not consider zero values to be null. It will decode to null, not zero, if null.
func FloatFromPtr ¶
FloatFromPtr creates a new Float that be null if f is nil.
func (Float) Equal ¶
Equal returns true if both floats have the same value or are both null. Warning: calculations using floating point numbers can result in different ways the numbers are stored in memory. Therefore, this function is not suitable to compare the result of a calculation. Use this method only to check if the value has changed in comparison to some previous value.
func (Float) IsZero ¶
IsZero returns true for invalid Floats, for future omitempty support (Go 1.4?) A non-null Float with a 0 value will not be considered zero.
func (Float) MarshalJSON ¶
MarshalJSON implements json.Marshaler. It will encode null if this Float is null.
func (Float) MarshalText ¶
MarshalText implements encoding.TextMarshaler. It will encode a blank string if this Float is null.
func (Float) Ptr ¶
Ptr returns a pointer to this Float's value, or a nil pointer if this Float is null.
func (*Float) UnmarshalJSON ¶
UnmarshalJSON implements json.Unmarshaler. It supports number and null input. 0 will not be considered a null Float.
func (*Float) UnmarshalText ¶
UnmarshalText implements encoding.TextUnmarshaler. It will unmarshal to a null Float if the input is blank. It will return an error if the input is not an integer, blank, or "null".
func (Float) ValueOrZero ¶
ValueOrZero returns the inner value if valid, otherwise zero.
type Int ¶
Int is an nullable int64. It does not consider zero values to be null. It will decode to null, not zero, if null.
func IntFromPtr ¶
IntFromPtr creates a new Int that be null if i is nil.
func (Int) IsZero ¶
IsZero returns true for invalid Ints, for future omitempty support (Go 1.4?) A non-null Int with a 0 value will not be considered zero.
func (Int) MarshalJSON ¶
MarshalJSON implements json.Marshaler. It will encode null if this Int is null.
func (Int) MarshalText ¶
MarshalText implements encoding.TextMarshaler. It will encode a blank string if this Int is null.
func (*Int) UnmarshalJSON ¶
UnmarshalJSON implements json.Unmarshaler. It supports number, string, and null input. 0 will not be considered a null Int.
func (*Int) UnmarshalText ¶
UnmarshalText implements encoding.TextUnmarshaler. It will unmarshal to a null Int if the input is blank. It will return an error if the input is not an integer, blank, or "null".
func (Int) ValueOrZero ¶
ValueOrZero returns the inner value if valid, otherwise zero.
type String ¶
type String struct {
sql.NullString
}
String is a nullable string. It supports SQL and JSON serialization. It will marshal to null if null. Blank string input will be considered null.
func StringFrom ¶
StringFrom creates a new String that will never be blank.
func StringFromPtr ¶
StringFromPtr creates a new String that be null if s is nil.
func (String) IsZero ¶
IsZero returns true for null strings, for potential future omitempty support.
func (String) MarshalJSON ¶
MarshalJSON implements json.Marshaler. It will encode null if this String is null.
func (String) MarshalText ¶
MarshalText implements encoding.TextMarshaler. It will encode a blank string when this String is null.
func (String) Ptr ¶
Ptr returns a pointer to this String's value, or a nil pointer if this String is null.
func (*String) UnmarshalJSON ¶
UnmarshalJSON implements json.Unmarshaler. It supports string and null input. Blank string input does not produce a null String.
func (*String) UnmarshalText ¶
UnmarshalText implements encoding.TextUnmarshaler. It will unmarshal to a null String if the input is a blank string.
func (String) ValueOrZero ¶
ValueOrZero returns the inner value if valid, otherwise zero.
type Time ¶
Time is a nullable time.Time. It supports SQL and JSON serialization. It will marshal to null if null.
func TimeFromPtr ¶
TimeFromPtr creates a new Time that will be null if t is nil.
func (Time) Equal ¶
Equal returns true if both Time objects encode the same time or are both null. Two times can be equal even if they are in different locations. For example, 6:00 +0200 CEST and 4:00 UTC are Equal.
func (Time) ExactEqual ¶
ExactEqual returns true if both Time objects are equal or both null. ExactEqual returns false for times that are in different locations or have a different monotonic clock reading.
func (Time) IsZero ¶
IsZero returns true for invalid Times, hopefully for future omitempty support. A non-null Time with a zero value will not be considered zero.
func (Time) MarshalJSON ¶
MarshalJSON implements json.Marshaler. It will encode null if this time is null.
func (Time) MarshalText ¶
MarshalText implements encoding.TextMarshaler. It returns an empty string if invalid, otherwise time.Time's MarshalText.
func (Time) Ptr ¶
Ptr returns a pointer to this Time's value, or a nil pointer if this Time is null.
func (*Time) UnmarshalJSON ¶
UnmarshalJSON implements json.Unmarshaler. It supports string and null input.
func (*Time) UnmarshalText ¶
UnmarshalText implements encoding.TextUnmarshaler. It has backwards compatibility with v3 in that the string "null" is considered equivalent to an empty string and unmarshaling will succeed. This may be removed in a future version.
func (Time) ValueOrZero ¶
ValueOrZero returns the inner value if valid, otherwise zero.
Source Files
Directories
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| Path | Synopsis |
|---|---|
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Package zero contains SQL types that consider zero input and null input to be equivalent with convenient support for JSON and text marshaling.
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Package zero contains SQL types that consider zero input and null input to be equivalent with convenient support for JSON and text marshaling. |